Soybean cultivar S52-U3

ABSTRACT

A novel soybean cultivar designated S52-U3 with high yield potential, tolerance to Roundup herbicide, early MG V maturity, and resistance to races 3, 9 and 14 of Soybean Cyst Nematode, further including the plants and seeds of the cultivar S52-U3, methods for producing a soybean plant by crossing the cultivar S52-U3 with itself or another soybean plant. The invention also relates to soybean cultivar S52-U3 further comprising one or more single gene traits, and to methods of producing a soybean having such traits by transformation or mutagenesis. The invention also includes using the soybean cultivar S52-U3 to produce other soybean cultivars or breeding lines.

FIELD OF THE INVENTION

[0001] The present invention is in the field of soybean breeding,specifically to a new and distinctive soybean cultivar, designatedS52-U3.

BACKGROUND OF THE INVENTION

[0002] The present invention relates to a new and distinctive soybeancultivar, designated S52-U3. There are numerous steps in the developmentof any novel, desirable plant germplasm. Plant breeding begins with theanalysis and definition of problems and weaknesses of the currentgermplasm, the establishment of program goals, and the definition ofspecific breeding objectives. The next step is selection of germplasmthat possess the traits to meet the program goals. The goal is tocombine in a single cultivar an improved combination of desirable traitsfrom the parental germplasm. These important traits may include higherseed yield, resistance to diseases and insects, better stems and roots,tolerance to drought and heat, and better agronomic quality.

[0003] Soybeans [Glycine max (L.) Merr.] are recognized to be naturallyself-pollinated plants, while capable of undergoing cross-pollination,rarely do so in nature. However, soybeans can be bred by bothself-pollination and cross-pollination techniques. Choice of breeding orselection methods depends on the mode of plant reproduction, theheritability of the trait(s) being improved, and the type of cultivarused commercially (e.g., F₁ hybrid cultivar, pureline cultivar, etc.).For highly heritable traits, a choice of superior individual plantsevaluated at a single location will be effective, whereas for traitswith low heritability, selection should be based on mean values obtainedfrom replicated evaluations of families of related plants. Popularselection methods commonly include pedigree selection, modified pedigreeselection, mass selection, and recurrent selection.

[0004] The complexity of inheritance influences choice of the breedingmethod. Backcross breeding is used to transfer one or a few favorablegenes for a highly heritable trait into a desirable cultivar. Thisapproach has been used extensively for breeding disease-resistantcultivars. Various recurrent selection techniques are used to improvequantitatively inherited traits controlled by numerous genes. The use ofrecurrent selection in self-pollinating crops depends on the ease ofpollination, the frequency of successful hybrids from each pollination,and the number of hybrid offspring from each successful cross.

[0005] Each breeding program should include a periodic, objectiveevaluation of the efficiency of the breeding procedure. Evaluationcriteria vary depending on the goal and objectives, but should includegain from selection per year based on comparisons to an appropriatestandard, overall value of the advanced breeding lines, and number ofsuccessful cultivars produced per unit of input (e.g., per year, perdollar expended, etc.).

[0006] Promising advanced breeding lines are thoroughly tested andcompared to appropriate standards in environments representative of thecommercial target area(s) for three or more years. The best lines arecandidates for new commercial cultivars; those still deficient in a fewtraits may be used as parents to produce new populations for furtherselection.

[0007] These processes, which lead to the final step of marketing anddistribution, usually take from eight to 12 years from the time thefirst cross is made. Therefore, development of new cultivars is atime-consuming process that requires precise forward planning, efficientuse of resources, and a minimum of changes in direction.

[0008] A most difficult task is the identification of individuals thatare genetically superior, because for most traits the true genotypicvalue is masked by other confounding plant traits or environmentalfactors. One method of identifying a superior plant is to observe itsperformance relative to other experimental plants and to a widely grownstandard cultivar. If a single observation is inconclusive, replicatedobservations provide a better estimate of its genetic worth.

[0009] The goal of a plant breeding is to develop new, unique andsuperior soybean cultivars and hybrids. The breeder initially selectsand crosses two or more parental lines, followed by repeated selfing andselection, producing many new genetic combinations. The breeder cantheoretically generate billions of different genetic combinations viacrossing, selfing and mutations. The breeder has no direct control atthe cellular level. Therefore, two breeders will never develop the sameline, or even very similar lines, having the same soybean traits.

[0010] Each year, the plant breeder selects the germplasm to advance tothe next generation. This germplasm is grown under unique and differentgeographical, climate and soil conditions, and further selections arethen made, during and at the end of the growing season. The cultivarsthat are developed are unpredictable. This unpredictability is becausethe breeder's selection occurs in unique environments, with no controlat the DNA level (using conventional breeding procedures), and withmillions of different possible genetic combinations being generated. Abreeder of ordinary skill in the art cannot predict the final resultinglines he develops, except possibly in a very gross and general fashion.The same breeder cannot produce the same cultivar twice by using theexact same original parents and the same selection techniques. Thisunpredictability results in the expenditure of large amounts of researchmonies to develop superior new soybean cultivars.

[0011] The development of new soybean cultivars requires the developmentand selection of soybean cultivars, the crossing of these cultivars andselection of superior hybrid crosses. The hybrid seed is produced bymanual crosses between selected male-fertile parents or by using malesterility systems. These hybrids are selected for certain single genetraits such as pod color, flower color, pubescence color or herbicideresistance which indicate that the seed is truly a hybrid. Additionaldata on parental lines as well as the phenotype of the hybrid influenceto breeder's decision whether to continue with the specific hybridcross.

[0012] Pedigree breeding and recurrent selection breeding methods areused to develop cultivars from breeding populations. Breeding programscombine desirable traits from two or more cultivars or variousbroad-based sources into breeding pools from which cultivars aredeveloped by selfing and selection of desired phenotypes. The newcultivars are evaluated to determine which have commercial potential.

[0013] Pedigree breeding is used commonly for the improvement ofself-pollinating crops. Two parents that possess favorable,complementary traits are crossed to produce an F₁. An F₂ population isproduced by selfing one or several F's. Selection of the bestindividuals may begin in the F₂ population; then, beginning in the F₃,the best individuals in the families are selected. Replicated testing offamilies can begin the F₄ generation to improve the effectiveness ofselection for traits with low heritability. At an advanced stage ofinbreeding (i.e., F₆ and F₇), the best lines or mixtures ofphenotypically similar lines are tested for potential release as newcultivars.

[0014] Mass and recurrent selections can be used to improve populationsof either self- or cross-pollinating crops. A genetically variablepopulation of heterozygous individuals is either identified or createdby intercrossing several different parents. The best plants are selectedbased on individual superiority, outstanding progeny, or excellentcombining ability. The selected plants are intercrossed to produce a newpopulation in which further cycles of selection are continued.

[0015] Backcross breeding has been used to transfer genes for a simplyinherited, highly heritable trait into a desirable homozygous cultivaror inbred line, which is the recurrent parent. The source of the traitto be transferred is called the donor parent. The resulting plant isexpected to have the attributes of the recurrent parent (e.g., cultivar)and the desirable trait transferred from the donor parent. After theinitial cross, individuals possessing the phenotype of the donor parentare selected and repeatedly crossed (backcrossed) to the recurrentparent. The resulting plant is expected to have the attributes of therecurrent parent (e.g., cultivar) and the desirable trait transferredfrom the donor parent.

[0016] The single-seed descent procedure in the strict sense refers toplanting a segregating population, harvesting a sample of one seed perplant, and using the one-seed sample to plant the next generation. Whenthe population has been advanced from the F₂ to the desired level ofinbreeding, the plants from which lines are derived will each trace todifferent F₂ individuals. The number of plants in a population declineseach generation due to failure of some seeds to germinate or some plantsto produce at least one seed. As a result, not all of the F₂ plantsoriginally sampled in the population will be represented by a progenywhen generation advance is completed.

[0017] In a multiple-seed procedure, soybean breeders commonly harvestone or more pods from each plant in a population and thresh themtogether to form a bulk. Part of the bulk is used to plant the nextgeneration and part is put in reserve. The procedure has been referredto as modified single-seed descent or the pod-bulk technique.

[0018] The multiple-seed procedure has been used to save labor atharvest. It is considerably faster to thresh pods with a machine than toremove one seed from each by hand for the single-seed procedure. Themultiple-seed procedure also makes it possible to plant the same numberof seeds of a population each generation of inbreeding. Enough seeds areharvested to make up for those plants that did not germinate or produceseed.

[0019] Descriptions of other breeding methods that are commonly used fordifferent traits and crops can be found in several reference books(e.g., Allard, 1960; Simmonds, 1979; Sneep et al., 1979; Fehr, 1987).

[0020] Proper testing should detect any major faults and establish thelevel of superiority or improvement over current cultivars. In additionto showing superior performance, there must be a demand for a newcultivar that is compatible with industry standards or which creates anew market. The introduction of a new cultivar will incur additionalcosts to the seed producer, the grower, processor and consumer, forspecial advertising and marketing, altered seed and commercialproduction practices, and new product utilization. The testingproceeding release of a new cultivar should take into considerationresearch and development costs as well as technical superiority of thefinal cultivar. For seed-propagated cultivars, it must be feasible toproduce seed easily and economically.

[0021] Soybean, [Glycine max (L.) Merr.], is an important and valuablefield crop. Thus, a continuing goal of plant breeders is to developstable, high yielding soybean cultivars that are agronomically sound.The reasons for this goal are obviously to maximize the amount of grainproduced on the land used and to supply food for both animals andhumans. To accomplish this goal, the soybean breeder must select anddevelop soybean plants that have the traits that result in superiorcultivars.

SUMMARY OF THE INVENTION

[0022] The present invention is a novel soybean cultivar designatedS52-U3 with high yield potential, tolerance to Roundup herbicide, earlyMG V maturity, and resistance to races 3, 9 and 14 of Soybean CystNematode. The invention relates to seeds of the cultivar S52-U3, plantsof the cultivar S52-U3, and to methods for producing a soybean plant bycrossing of the cultivar S52-U3 with itself or with another soybeangenotype.

[0023] The invention is also directed to soybean cultivar S52-U3 furthercomprising one or more specific, single gene traits, for exampletransgenes, and which has essentially all of the morphological andphysiological characteristics of cultivar S52-U3. The invention furtherrelates to seeds of cultivar S52-U3 further comprising one or morespecific, single gene traits. The invention also relates to plants ofcultivar S52-U3 further comprising one or more specific, single genetraits. The invention includes methods for producing a soybean plant bycrossing the soybean plant of cultivar S52-U3 further comprising one ormore specific, single gene traits with itself or with another soybeangenotype.

[0024] The invention is further directed to methods for producing asoybean plant by crossing a first parent soybean plant with a secondparent soybean plant, wherein the first or second soybean plant is thesoybean plant from the soybean line S52-U3. Further, both first andsecond parent soybean plants may be from the soybean cultivar S52-U3.Therefore, any methods using the soybean cultivar S52-U3 are part ofthis invention: selfing, backcrosses, hybrid breeding and crosses topopulations. All plants produced using soybean cultivar S52-U3 as aparent are within the scope of the invention.

DEFINITIONS

[0025] In the description and tables that follow, a number of terms areused. In order to provide a clear and consistent understanding of thespecification and claims, including the scope to be given such terms,the following definitions are provided:

[0026] Hypocotyl. A hypocotyl is the portion of an embryo or seedlingbetween the cotyledons and the root. Therefore, it can be considered atransition zone between shoot and root.

[0027] Lodging Resistance. Lodging is rated on a scale of 1 to 9. Whereone is completely upright and 9 is completely prostrate.

[0028] Maturity Date. Plants are considered mature when 95% of the podshave reached their mature color.

[0029] Phytophthora Root Rot Field Tolerance Score (PRR). PRR does notrelate to race-specific vertical resistance, such as rps-1k or Rps6, butto horizontal, non-race specific resistance.

[0030] Plant Height. Plant height is taken from the top of soil to topof node of the plant and is measured in centimeters.

[0031] Pod. This refers to the fruit of a soybean plant. It consists ofthe hull or shell (pericarp) and the soybean seeds.

[0032] Pubescence. This refers to a covering of very fine hairs closelyarranged on the leaves, stems and pods of the soybean plant.

[0033] Seed Yield (Bushels/Acre). The yield in bushels/acre is theactual yield of the grain at harvest.

DETAILED DESCRIPTION OF THE INVENTION

[0034] A soybean cultivar needs to be highly homogeneous, homozygous andreproducible to be useful as a commercial cultivar. There are manyanalytical methods available to determine the homozygotic and phenotypicstability of these cultivars.

[0035] The oldest and most traditional method of analysis is theobservation of phenotypic traits. The data is usually collected in fieldexperiments over the life of the soybean plants to be examined.Phenotypic characteristics most often observed are for traits associatedwith seed yield, lodging resistance, disease resistance, emergence,maturity, plant height, shattering, flower color, pubescence color, podcolor and hilum color.

[0036] In addition to phenotypic observations, the genotype of a plantcan also be examined. There are many laboratory-based techniquesavailable for the analysis, comparison and characterization of plantgenotype; among these are Isozyme Electrophoresis, Restriction FragmentLength Polymorphisms (RFLPs), Randomly Amplified Polymorphic DNAs(RAPDs), Arbitrarily Primed Polymerase Chain Reaction (AP-PCR), DNAAmplification Fingerprinting (DAF), Sequence Characterized AmplifiedRegions (SCARs), Amplified Fragment Length Polymorphisms (AFLPs), andSimple Sequence Repeats (SSRs) which are also referred to asMicrosatellites.

[0037] The cultivar of the invention has shown uniformity and stabilityfor all traits, as described in the following cultivar descriptioninformation. It has been self-pollinated a sufficient number ofgenerations, with careful attention to uniformity of plant type toensure homozygosity and phenotypic stability. The line has beenincreased with continued observation for uniformity. No variant traitshave been observed or are expected in S52-U3. Soybean cultivar S52-U3,being substantially homozygous, can be reproduced by planting seeds ofthe line, growing the resulting soybean plants under self-pollinating orsib-pollinating conditions, and harvesting the resulting seed, usingtechniques familiar to the agricultural arts.

[0038] Publications useful as references in interpreting the datapresented below include: Caldwell, B. E. ed. 1973. “Soybeans:Improvement, Production, and Uses” Amer. Soc. Agron. Monograph No. 16;Buttery, B. R., and R. I. Buzzell 1968. “Peroxidase Activity in Seed ofSoybean Varieties” Crop Sci. 8: 722-725; Hymowitz, T. 1973.“Electrophoretic analysis of SBTI-A2 in the USDA Soybean GermplasmCollection” Crop Sci., 13: 420-421; Payne R. C., and L. F. Morris, 1976.“Differentiation of Soybean Varieties by Seedling Pigmentation Patterns”J. Seed. Technol. 1: 1-19. The disclosures of which are eachincorporated by reference in their entirety.

[0039] Soybean cultivar S52-U3 has the following morphological and othercharacteristics: Flower Color White Pubescence Color Gray Pod Color TanHilum Color Buff Seed Coat Color Yellow Leaf Shape Ovate StemTermination Determinate Plant Type Intermediate Hypocotyl Color GreenMaturity Group V Relative Maturity 5.2 Soybean Cyst Nematode Resistant(R 3, 9, 14) Southern Stem Canker Moderate Resistance Hypocotyl LengthLong

[0040] The invention is further directed to methods for producing asoybean plant by crossing a first parent soybean plant with a secondparent soybean plant, wherein the first or second soybean plant is thesoybean plant from the soybean line S52-U3. Further, both first andsecond parent soybean plants may be from the soybean cultivar S52-U3.Therefore, any methods using the soybean cultivar S52-U3 are part ofthis invention: selfing, backcrosses, hybrid breeding and crosses topopulations. All plants produced using soybean cultivar S52-U3 as aparent are within the scope of the invention.

[0041] The invention also encompasses plants of cultivar S52-U3 andparts thereof further comprising one or more specific, single genetransferred traits. Such traits are introgressed into cultivar S52-U3from another soybean cultivar or are directly transformed into cultivarS52-U3. Preferably, one or more new traits are transferred to cultivarS52-U3, or, alternatively, one or more traits of cultivar S52-U3 arealtered or substituted. The introgression of the trait(s) into cultivarS52-U3 is for example achieved by recurrent selection breeding, forexample by backcrossing. The goal of a backcross protocol is to alter orsubstitute a single trait or characteristic in the original inbred. Inone embodiment of the present invention, cultivar S52-U3 (the recurrentparent) is first crossed to a donor inbred (the non-recurrent parent)that carries the appropriate gene(s) for the trait(s) in question. Theprogeny of this cross is then mated back to the recurrent parentfollowed by selection in the resultant progeny for the desired trait(s)to be transferred from the non-recurrent parent. After three, preferablyfour, more preferably five or more generations of backcrosses with therecurrent parent with selection for the desired trait(s), the progenywill be heterozygous for loci controlling the trait(s) beingtransferred, but will be like the recurrent parent for most or almostall other genes, i.e., will be like the recurrent parent for essentiallyall of the recurrent parent's physiological and morphologicalcharacteristics. (see, for example, Poehlman & Sleper (1995) BreedingField Crops, 4th Ed., 172-175; Fehr (1987) Principles of CultivarDevelopment, Vol. 1: Theory and Technique, 360-376).

[0042] The laboratory-based techniques described above, in particularRFLP and SSR, can be used in such backcrosses to identify the progenieshaving the highest degree of genetic identity with the recurrent parent.This permits one to accelerate the production of soybean cultivarshaving at least 90%, preferably at least 95%, more preferably at least99% genetic identity with the recurrent parent, yet more preferablygenetically identical to the recurrent parent, and further comprisingthe trait(s) introgressed from the donor patent. Such determination ofgenetic identity can be based on molecular markers used in thelaboratory-based techniques described above.

[0043] The last backcross generation is then selfed to give purebreeding progeny for the gene(s) being transferred. The resulting plantshave essentially all of the morphological and physiologicalcharacteristics of cultivar S52-U3, in addition to the single genetrait(s) transferred to the inbred. The exact backcrossing protocol willdepend on the trait being altered to determine an appropriate testingprotocol. Although backcrossing methods are simplified when the traitbeing transferred is a dominant allele, a recessive allele may also betransferred. In this instance it may be necessary to introduce a test ofthe progeny to determine if the desired trait has been successfullytransferred.

[0044] The cultivar of the invention can also be used for transformationwhere exogenous genes are introduced and expressed by the cultivar ofthe invention. Genetic variants created either through traditionalbreeding methods using cultivar S52-U3 or through transformation ofcultivar S52-U3 by any of a number of protocols known to those of skillin the art are intended to be within the scope of this invention (seee.g. Trick et al. (1997) Recent advances in soybean transformation, inPlant Tissue Culture and Biotechnology, 3:9-26, incorporated herein byreference).

[0045] Production of a genetically modified plant tissue bytransformation combines teachings of the present disclosure with avariety of techniques and expedients known in the art. In most instancesalternate expedients exist for each stage of the overall process. Thechoice of expedients depends on the variables such as the plasmid vectorsystem chosen for the cloning and introduction of the desiredrecombinant DNA molecule, as well as the particular structural gene,promoter elements and upstream elements used. Persons skilled in the artare able to select and use appropriate alternatives to achievefunctionality. Culture conditions for expressing desired structuralgenes and cultured cells are known in the art. Also as known in the art,soybeans are transformable and regenerable such that whole plantscontaining and expressing desired genes under regulatory control may beobtained. General descriptions of plant expression vectors and reportergenes and transformation protocols can be found in Gruber, et al.,“Vectors for Plant Transformation, in Methods in Plant Molecular Biology& Biotechnology” in Glich et al., (Eds. pp. 89-119, CRC Press, 1993).Moreover GUS expression vectors and GUS gene cassettes are availablefrom Clone Tech Laboratories, Inc., Palo Alto, Calif. while luciferaseexpression vectors and luciferase gene cassettes are available from ProMega Corp. (Madison, Wis.). General methods of culturing plant tissuesare provided for example by Maki et al. “Procedures for IntroducingForeign DNA into Plants” in Methods in Plant Molecular Biology &Biotechnology, Glich et al. (Eds. pp. 67-88 CRC Press, 1993); and byPhillips et al. “Cell-Tissue Culture and In-Vitro Manipulation” inSoybean & Soybean Improvement, 3rd Edition Sprague et al. (Eds. pp.345-387) American Society of Agronomy Inc. et al. 1988.

[0046] Methods of introducing desired recombinant DNA molecule intoplant tissue include the direct infection or co-cultivation of plantcells with Agrobacterium tumefaciens, Horsch et al., Science, 227:1229(1985). Descriptions of Agrobacterium vector systems and methods forAgrobacterium-mediated gene transfer provided by Gruber, et al. supra.Other useful methods include but are not limited to expression vectorsintroduced into plant tissues using a direct gene transfer method suchas microprojectile-mediated delivery, DNA injection, electroporation andthe like. More preferably expression vectors are introduced into planttissues using the biolistic microprojectile delivery orAgrobacterium-medicated transformation. Transformed plants obtained viaprotoplast transformation are also intended to be within the scope ofthis invention.

[0047] Many traits have been identified that are not regularly selectedfor in the development of a new cultivar but that can be improved e.g.by backcrossing techniques or by genetic transformation. Using materialsand methods well known to those persons skilled in the art, traits thatare capable of being transferred, to cultivar S52-U3 include, but arenot limited to, herbicide tolerance, resistance for bacterial, fungal,or viral disease, nematode resistance, insect resistance, enhancednutritional quality, such as oil, starch and protein content or quality,improved performance in an industrial process, altered reproductivecapability, such as male sterility or male fertility, yield stabilityand yield enhancement. Other traits transferred to cultivar S52-U3 arefor the production of commercially valuable enzymes or metabolites inplants of cultivar S52-U3.

[0048] Traits capable of being transferred to soybean cultivar S52-U3are naturally occurring soybean traits or transgenic traits. Transgenesare directly introduced into cultivar S52-U3 using genetic engineeringand transformation techniques well known in the art, some of which aredescribed above, or are originally introduced into a donor,non-recurrent parent using genetic engineering and transformationtechniques, which are then introgressed into cultivar S52-U3, forexample by backcrossing. A transgene typically comprises a nucleotidesequence whose expression is responsible or contributes to the trait,under the control of a promoter capable of directing the expression ofthe nucleotide sequence at the desired time in the desired tissue orpart of the plant. Constitutive, tissue-specific or inducible promoterspreferably are used. The transgene may also comprise other regulatoryelements such as for example translation enhancers or terminationsignals. In one embodiment of the present invention, the transgenenucleotide sequence in the cultivar S52-U3 includes a coding sequencethat is transcribed and translated into a protein. In another embodimentof the invention, the nucleotide sequence encodes an antisense RNA or asense RNA that is not translated or only partially translated.

[0049] Where more than one trait are introgressed into cultivar S52-U3,it is preferred that the specific genes are all located at the samegenomic locus in the donor, non-recurrent parent, preferably, in thecase of transgenes, as part of a single DNA construct integrated intothe donor's genome. Alternatively, if the genes are located at differentgenomic loci in the donor, non-recurrent parent, backcrossing allows torecover essentially all of the morphological and physiologicalcharacteristics of cultivar S52-U3 in addition to the multiple genes inthe resulting soybean cultivar.

[0050] The genes responsible for a specific, single gene trait aregenerally inherited through the nucleus. Known exceptions are, e.g. thegenes for male sterility, some of which are inherited cytoplasmically,but still act as single gene traits. In a preferred embodiment, atransgene to be introgressed into cultivar S52-U3 is integrated into thenuclear genome of the donor, non-recurrent parent or the transgene isdirectly transformed into the nuclear genome of cultivar S52-U3. Inanother preferred embodiment, a transgene to be introgressed intocultivar S52-U3 is integrated into the plastid genome of the donor,non-recurrent parent or the transgene is directly transformed into theplastid genome of cultivar S52-U3. In a preferred embodiment, a plastidtransgene comprises one gene transcribed from a single promoter or twoor more genes transcribed from a single promoter.

[0051] A non-exclusive list of traits or nucleotide sequences capable ofbeing transferred into cultivar S52-U3, using material and methods wellknown to those persons skilled in the art are as follows: geneticfactor(s) responsible for resistance to brown stem rot (U.S. Pat. No.5,689,035) or resistance to cyst nematodes (U.S. Pat. No. 5,491,081); atransgene encoding an insecticidal protein, such as, for example, acrystal protein of Bacillus thuringiensis or a vegetative insecticidalprotein from Bacillus cereus, such as VIP3 (see for example Estruch etal. Nat Biotechnol (1997) 15:137-41; a herbicide tolerance transgenewhose expression renders plants of cultivar S52-U3 tolerant to theherbicide, for example, expression of an altered acetohydroxyacidsynthase (AHAS) enzyme confers upon plants tolerance to variousimidazolinone or sulfonamide herbicides (U.S. Pat. No. 4,761,373). Othersuch traits include, for example, a non-transgenic trait conferring tocultivar S52-U3 tolerance to imidazolinones or sulfonylurea herbicides;a transgene encoding a mutant acetolactate synthase (ALS) that renderthe plants resistant to inhibition by sulfonylurea herbicides (U.S. Pat.No. 5,013,659); a gene encoding a mutant glutamine synthetase (GS)resistant to inhibition by herbicides that are known to inhibit GS, e.g.phosphinothricin and methionine sulfoximine (U.S. Pat. No. 4,975,374);and a Streptomyces bar gene encoding a phosphinothricin acetyltransferase resulting in tolerance to the herbicide phosphinothricin orglufosinate (U.S. Pat. No. 5,489,520). Other traits capable of beingtransferred to the cultivar S52-U3 of the invention include tolerationto inhibition by cyclohexanedione and aryloxyphenoxypropanoic acidherbicides (U.S. Pat. No. 5,162,602), which is conferred by an alteredacetyl coenzyme A carboxylase(ACCase); transgenic glyphosate tolerantplants, which tolerance is conferred by an altered5-enolpyruvyl-3-phosphoshikimate (EPSP) synthase gene; tolerance to aprotoporphyrinogen oxidase inhibitor, which is achieved by expression ofa tolerant protoporphyrinogen oxidase enzyme in plants (U.S. Pat. No.5,767,373). In yet another embodiment of the present invention, atransgene introgressed into cultivar S52-U3 comprises a gene conferringtolerance to a herbicide and at least another nucleotide sequence foranother trait, such as for example, insect resistance or tolerance toanother herbicide.

[0052] Direct selection may be applied where the trait acts as adominant trait. An example of a dominant trait is herbicide tolerance.For this selection process, the progeny of the initial cross are sprayedwith the herbicide prior to the backcrossing. The spraying eliminatesany plant which do not have the desired herbicide tolerancecharacteristic, and only those plants which have the herbicide tolerancegene are used in the subsequent backcross. This process is then repeatedfor the additional backcross generations.

[0053] This invention is also directed to methods for producing asoybean plant by crossing a first parent soybean plant with a secondparent soybean plant, wherein the first or second soybean plant is thesoybean plant from the line S52-U3. Further, both first and secondparent soybean plants may be from the cultivar S52-U3. Therefore, anymethods using the cultivar S52-U3 are part of this invention: selfing,backcrosses, hybrid breeding, and crosses to populations. Any plantsproduced using cultivar S52-U3 or cultivar S52-U3 further comprising oneor more specific, single gene traits as a parent are within the scope ofthis invention. For example, the soybean cultivar S52-U3 or cultivarS52-U3 further comprising one or more specific, single gene traits areused in crosses with other, different, soybean plants to produce firstgeneration (F1) soybean hybrid seeds and plants with superiorcharacteristics. For example, a method to produce a hybrid soybean seedcomprises the steps of planting, preferably in pollinating proximity,seeds of soybean cultivar S52-U3 or seeds of soybean cultivar S52-U3further comprising one or more specific, single gene traits and anothersoybean cultivar, cultivating the soybean plants resulting from saidseeds until said plants bear flowers, emasculating the plants of eitherone or the other soybean cultivar, inducing cross pollination to occurbetween said soybean cultivars and harvesting seeds produced on saidemasculated plants of the cultivar line.

[0054] As used herein, the term “plant” includes plant cells, plantprotoplasts, plant cells of tissue culture from which soybean plants canbe regenerated, plant calli, plant clumps, and plant cells that areintact in plants or parts of plants, such as pollen, flowers, seeds,pods, leaves, stems, and the like. Thus, another aspect of thisinvention is to provide for cells that upon growth and differentiationproduce the cultivar S52-U3.

[0055] Further reproduction of the cultivar can occur by tissue cultureand regeneration. Tissue culture of various tissues of soybeans andregeneration of plants therefrom is well known and widely published. Forexample, reference may be had to Komatsuda, T. et al., “Genotype XSucrose Interactions for Somatic Embryogenesis in Soybean,” Crop Sci.31:333-337 (1991); Stephens, P. A. et al., “Agronomic Evaluation ofTissue-Culture-Derived Soybean Plants,” Theor. Appl. Genet. (1991)82:633-635; Komatsuda, T. et al., “Maturation and Germination of SomaticEmbryos as Affected by Sucrose and Plant Growth Regulators in SoybeansGlycine gracilis Skvortz and Glycine max (L.) Merr.,” Plant Cell, Tissueand Organ Culture, 28:103-113 (1992); Dhir, S. et al., “Regeneration ofFertile Plants from Protoplasts of Soybean (Glycine max L. Merr.):Genotypic Differences in Culture Response,” Plant Cell Reports (1992)11:285-289; Pandey, P. et al., “Plant Regeneration from Leaf andHypocotyl Explants of Glycine wightii (W. and A.) VERDC. varlongicauda,” Japan J. Breed. 42:1-5 (1992); and Shetty, K., et al.,“Stimulation of In Vitro Shoot Organogenesis in Glycine max (Merrill.)by Allantoin and Amides,” Plant Science 81:(1992) 245-251; as well asU.S. Pat. No. 5,024,944, issued Jun. 18, 1991 to Collins et al. and U.S.Pat. No. 5,008,200, issued Apr. 16, 1991 to Ranch et al. Thus, anotheraspect of this invention is to provide cells which upon growth anddifferentiation produce soybean plants having all or essentially all thephysiological and morphological characteristics of cultivar S52-U3. Thedisclosures, publications, and patents which are disclosed herein areall hereby incorporated herein in their entirety by reference.

INDUSTRIAL APPLICABILITY

[0056] The seed of soybean cultivar S52-U3 further comprising one ormore specific, single gene traits, the plant produced from the seed, thehybrid soybean plant produced from the crossing of the cultivar with anyother soybean plant, hybrid seed, and various parts of the hybridsoybean plant can be utilized for human food, livestock feed, and as araw material in industry.

[0057] Soybean is the world's leading source of vegetable oil andprotein meal. The oil extracted from soybeans is used for cooking oil,margarine, and salad dressings. Soybean oil is composed of saturated,monounsaturated and polyunsaturated fatty acids. It has a typicalcomposition of 11% palmitic, 4% stearic, 25% oleic, 50% linoleic and 9%linolenic fatty acid content (“Economic Implications of Modified SoybeanTraits Summary Report”, Iowa Soybean Promotion Board & American SoybeanAssociation Special Report 92S, May 1990. Changes in fatty acidcomposition for improved oxidative stability and nutrition areconstantly sought after. Industrial uses of soybean oil which issubjected to further processing include ingredients for paints,plastics, fibers, detergents, cosmetics, and lubricants. Soybean oil maybe split, inter-esterified, sulfurized, epoxidized, polymerized,ethoxylated, or cleaved. Designing and producing soybean oil derivativeswith improved functionality, oliochemistry, is a rapidly growing field.The typical mixture of triglycerides is usually split and separated intopure fatty acids, which are then combined with petroleum-derivedalcohols or acids, nitrogen, sulfonates, chlorine, or with fattyalcohols derived from fats and oils.

[0058] Soybean is also used as a food source for both animals andhumans. Soybean is widely used as a source of protein for animal feedsfor poultry, swine and cattle. During processing of whole soybeans, thefibrous hull is removed and the oil is extracted. The remaining soybeanmeal is a combination of carbohydrates and approximately 50% protein.For human consumption soybean meal is made into soybean flour which isprocessed to protein concentrates used for meat extenders or specialtypet foods. Production of edible protein ingredients from soybean offersa healthy, less expensive replacement for animal protein in meats aswell as dairy-type products. TABLE Comparison Between S52-U3 andSyngenta 3474, Syngenta S51-T1, Syngenta S53-Q7 and Pioneer 9511Cultivar/Trait Yield Maturity Lodging Height PRR IC SDS R3 R14 S52-U342.7 10-6 3.6 88 3.5 4.3 4.0 R R Syngenta 44.0  9-26 4.5 105 3.3 7.3 2.1S S 3474 Syngenta 37.7 10-5 4.2 128 3.8 5.3 4.4 MR S S51-T1 Syngenta38.6 10-7 2.5 90 4.5 2.5 3.5 R MR S53-Q7 Pioneer 9511 42.0 10-3 2.8 1134.2 3.8 5.0 Grand Mean 41.0 3.5 105 3.9 4.6 3.8 No. of Tests 37 17 20 232 2 3 LSD (0.05) 2.7  2 0.7 7 2.9 3.1 2.6

Deposit Information

[0059] Applicants have made a deposit of at least 2500 seeds of thecultivar of the present invention with the American Type CultureCollection (ATCC), Manassas, Va., 20110-2209 U.S.A., ATCC AccessionNumber No:______. This deposit of cultivar S52-U3 will be maintained inthe ATCC depository, which is a public depository, for a period of 30years, or 5 years after the most recent request, or for the effectivelife of the patent, whichever is longer, and will be replaced if itbecomes nonviable during that period. Additionally, Applicants havesatisfied all the requirements of 37 C.F.R. §§1.801-1.809, includingproviding an indication of the viability of the sample. Applicantsimpose no restrictions on the availability of the deposited materialfrom the ATCC; however, Applicants have no authority to waive anyrestrictions imposed by law on the transfer of biological material orits transportation in commerce. Applicants do not waive any infringementof its rights granted under this patent or under the Plant VarietyProtection Act (7 USC 2321 et seq.).

[0060] The foregoing invention has been described in detail by way ofillustration and example for purposes of clarity and understanding.However, it will be obvious that certain changes and modifications suchas single gene modifications and mutations, somaclonal variants, variantindividuals selected from large populations of the plants of the instantinbred and the like may be practiced within the scope of the invention,as limited only by the scope of the appended claims.

What is claimed is: 1) Seed of soybean cultivar S52-U3 having beendeposited under ATCC Accession No:______. 2) A soybean plant, or partsthereof, of cultivar S52-U3, seed of said cultivar having been depositedunder ATCC Accession No:______. 3) Pollen of the plant of claim
 2. 4) Anovule of the plant of claim
 2. 5) A soybean plant, or parts thereof,having all the physiological and morphological characteristics of aplant according to claim
 2. 6) A male sterile soybean plant, or partsthereof, otherwise having all the physiological and morphologicalcharacteristics of a plant according to claim
 2. 7) A soybean plant, orparts thereof, having essentially all the physiological andmorphological characteristics of a plant according to claim 2, andfurther comprising one or more single gene transferred traits. 8) Seedsof a plant according to claim
 7. 9) A soybean plant, or parts thereof,according to claim 2, wherein the plant or parts thereof have beentransformed so that its genetic material contains one or more transgenesoperably linked to one or more regulatory elements. 10) A soybean plantaccording to claim 9, wherein said transgene comprises a gene conferringupon said soybean plant tolerance to a herbicide. 11) A soybean plantaccording to claim 10, wherein said herbicide is glyphosate,glufosinate, a sulfonylurea or an imidazolinone herbicide, or aprotoporphyrinogen oxidase inhibitor. 12) A soybean plant according toclaim 9, wherein said transgene comprises a gene conferring upon saidsoybean plant insect resistance, disease resistance, nematode resistanceor virus resistance. 13) A soybean plant according to claim 12, whereinsaid gene conferring upon said soybean plant insect resistance comprisesa VIP3 gene. 14) A tissue culture of regenerable cells of a soybeanplant according to claim 2, wherein the tissue regenerates plantscapable of expressing all the morphological and physiologicalcharacteristics of a plant according to claim
 2. 15) A soybean plantregenerated from the tissue culture of claim 14, capable of expressingall the morphological and physiological characteristics of cultivarS52-U3, representative seed of said cultivar having been deposited underATCC Accession No:______. 16) A tissue culture according to claim 14,the cells or protoplasts of the tissue culture being from a tissueselected from the group comprising of leaves, pollen, embryos, roots,flowers, seeds, pods, and stems. 17) A method for producing a soybeanseed comprising crossing a first parent soybean plant with a secondparent soybean plant and harvesting the resultant first generationsoybean seed, wherein said first or second parent soybean plant is asoybean plant according to claim 2 or a soybean plant having all thephysiological and morphological characteristics of a plant according toclaim
 2. 18) A method according to claim 17, wherein said first parentsoybean plant is different from said second parent soybean plant,wherein said resultant seed is a first generation (F1) hybrid soybeanseed. 19) A method according to claim 17, wherein said soybean plant ofcultivar S52-U3, or said soybean plant having all the physiological andmorphological characteristics of a plant of cultivar S52-U3, is thefemale parent. 20) A method according to claim 17, wherein said soybeanplant of cultivar S52-U3, or said soybean plant having all thephysiological and morphological characteristics of a plant of cultivarS52-U3, is the male parent. 21) An F1 hybrid soybean seed produced bythe method of claim
 18. 22) An F1 hybrid soybean plant, or partsthereof, grown from the seed of claim
 21. 23) A method for producingsoybean seed comprising crossing a first parent soybean plant with asecond parent soybean plant and harvesting the resultant firstgeneration soybean seed, wherein said first or second parent soybeanplant is a soybean plant according to claim
 7. 24) A method according toclaim 23, wherein said first parent soybean plant is different from saidsecond parent soybean plant, wherein said resultant seed is a firstgeneration (F1) hybrid soybean seed. 25) An F1 hybrid soybean seedproduced by the method of claim
 23. 26) An F1 hybrid soybean plant, orparts thereof, grown from the seed of claim
 25. 27) A method to producea hybrid soybean seed comprising the steps of: a) planting the seed ofsoybean cultivar S52-U3, seed of said cultivar having been depositedunder ATCC Accession No:______, or seeds of a soybean plant havingessentially all the physiological and morphological characteristics of aplant of cultivar S52-U3, and seeds of another soybean cultivar; b)cultivating soybean plants resulting from said seeds until said plantsbear flowers; c) emasculating the male flowers of the plants of eithersoybean cultivar; d) inducing cross pollination to occur between saidsoybean cultivars; and e) harvesting seeds produced on said emasculatedplants of the cultivar. 28) A first generation (F1) hybrid soybean plantproduced by growing said hybrid soybean seed of claim
 27. 29) A methodfor developing a soybean plant in a soybean breeding program using plantbreeding techniques, which include employing a soybean plant, or itsparts thereof, as a source of breeding material, comprising: using thesoybean plant, or its parts thereof, of claim 2 as a source of breedingmaterial. 30) The soybean breeding program of claim 31, wherein plantbreeding techniques are selected from the group of: recurrent selection,backcrossing, pedigree breeding, restriction fragment lengthpolymorphism enhanced selection, genetic marker enhanced selection, andtransformation. 31) A soybean plant according to claim 7, wherein saidone or more single gene transferred traits comprise a gene which isfirst introduced by transgenic methods into a soybean cultivar differentfrom said soybean cultivar S52-U3 and then introgressed into saidsoybean cultivar S52-U3. 32) A method for producing cultivar S52-U3,representative seed of which have been deposited under ATCC AccessionNo.______, comprising: a) planting a collection of seed comprising seedof a hybrid, one of whose parents is cultivar S52-U3, said collectionalso comprising seed of said cultivar; b) growing plants from saidcollection of seed; c) identifying inbred parent plants; d) controllingpollination in a manner which preserves the homozygosity of said inbredparent plant; and e) harvesting the resultant seed. 33) A S52-U3-derivedsoybean plant, or parts thereof, produced by the method of claim 27,said S52-U3-derived soybean plant expressing a combination of at leasttwo S52-U3 traits selected from the group consisting of: high yieldpotential, resistance to Soybean Cyst Nematode, moderate resistance toSouthern Stem Canker, a Relative Maturity rating of 5.2 (early MG VMaturity), adaptation to the Mid-South, the Southeast, and to easternKansas/southwestern Missouri, and excellent emergence and lodgingresistance. 34) The method of claim 33, further comprising: a) crossingsaid S52-U3-derived soybean plant with itself or another soybean plantto yield additional S52-U3-derived progeny soybean seed; b) growing saidprogeny soybean seed of step (a) under plant growth conditions, to yieldadditional S52-U3-derived soybean plants; and c) repeating the crossingand growing steps of (a) and (b) from 0 to 7 times to generate furtherS52-U3-derived soybean plants. 35) The further S52-U3-derived soybeanplant, or parts thereof, of claim 33, wherein said furtherS52-U3-derived soybean plant, or parts thereof, express a combination ofat least two S52-U3 traits selected from the group consisting of: highyield potential, resistance to Soybean Cyst Nematode, moderateresistance to Southern Stem Canker, a Relative Maturity rating of 5.2(early MG V Maturity), adaptation to the Mid-South, the Southeast, andto eastern Kansas/southwestern Missouri, and excellent emergence andlodging resistance.